The present invention relates to computerized label printing, and particularly to apparatus for printing on a label of portions of a screen display generated by an application program running on a host computer.
Word processors and similar equipment utilizing personal computers are currently in widespread use. Most printing is done on pin feed forms, wherein perforations on the edges of the paper are engaged by sprocket wheels. When correspondence is printed using any of a number of different word processing programs, the envelope for the correspondence must be separately addressed by printing directly on the envelope or by printing a label and affixing the label to the envelope.
While many printers can print on an envelope, such printing is a complicated process. The pin feed paper must first be removed, an envelope is required to be inserted and software commands are needed to align the text correctly. After the envelope is printed, pin feed paper is reinserted into the printer. This process is time consuming and mistakes can easily occur including misalignment of text, transcription errors, and jamming of envelopes and pin feed paper. For this reason, it is a common practice to address the envelope manually with the aid of a typewriter or by pen and hand, practices antithetical to the use of efficient computers.
Alternatively, pin feed labels or pin feed envelopes may be used. However, although the labels and envelopes are fed automatically, the time needed to set up the forms and the necessary software commands to be implemented is so great that their use is justified only if many addresses need to be printed.
There is thus a need in the prior art for devices capable of efficient printing of labels without requiring expensive apparatus or time consuming setup procedures.
U.S. Pat. No. 4,569,610 to Drejza (marketed by IBM under the trade designation "Proprinter"), describes a machine capable of the simultaneous feeding of both primary and secondary documents while printing on only the secondary documents. In such a manner, a user is able to insert an envelope into a special slot without removing the pin feed paper. However, this printer cannot label any object thicker or larger than standard sized envelopes. Moreover, it is a full sized, medium priced, machine which is of little use to those who already own computer printers. Also, because the two documents must be simultaneously fed, a full page of paper is wasted each time a secondary document is printed.
Another approach to printing of addresses disclosed in "Simultaneous Document and Address Label Printing", IBM Technical Disclosure Bulletin, Vol. 28, No. 2, July 1985 uses a special carbon film coated label attached by a temporary adhesive to the rear of the pin feed paper in the area of the addressee heading. After printing a letter on the specialized paper, the label is removed and attached to an envelope. However, this system works only with impact printers, demands perfect alignment of the addressee heading and the label, and is restricted to printing only an exact duplicate of the letter heading. Moreover, labels with a temporary adhesive are likely to peel prematurely, causing paper jams in the printer.
U.S. Pat. No. 4,262,591 to Cook describes a dedicated label printing device which is a stand alone machine including its own computer with a keyboard, display and magnetic data storage mechanism. This device thus duplicates features found in personal computers, and, importantly, no means is provided to enable the device to be interfaced with a host computer running a variety of programs, each requiring a label to be printed.
There is accordingly a need in the prior art for devices capable of interacting with a host computer for printing a designated field from any portion of a document, without duplicating expensive components incorporated in the host computer.
Although certain word processing programs are marketed with features enabling selection of a specified field for printing on an envelope, for example, these features are limited to operation only with the particular word processor. Thus, if a portion of a spreadsheet or database from a different program is to be printed, or if a different word processor is loaded into the computer and it is necessary to print an envelope or label according to a selected address field or the like, the desired feature is lost and the previously described inefficient and complex approaches must be used. Such a system is marketed under the designation "Q & A", and was reported in the New York Times of Sunday, Mar. 9, 1986, at page 16F. As described therein, the program automatically abstracts an address field by finding the first line of text beginning in the left hand margin and not ending in two or more digits. All following flush left lines, until the first blank line, are considered to be the address field to be printed on the envelope. Apparently, however, the envelope must be inserted in the standard printer of the computer executing the program, thus interrupting the flow of program operation.
Significantly, none of these programs momentarily interrupt existing operating programs, pause the same, and provide an output for printing independently of the operating program, thereafter reinstating the program to its previous state by use of the DOS interrupt. These program or DOS interruptions can take place in a fraction of a second so that the user is not inconvenienced. None of the programs are provided for operation with any other program, such as a word processing program, and none of the prior art provide separate, resident, overlay programs which may be used for constantly monitoring the screen display to capture and output a particular field based on a predetermined criterion. Rather, they may be part of one particular operating program, are lost when the program is no longer running, and cannot be made to operate with other programs.
Accordingly, applicants have recognized a need in the prior art for implementation of a label printing feature which is not program dependent and which is operative for documents produced by application programs and which does not disrupt normal computer or printing operations.
In another consideration, the use of machine readable bar codes is a rapidly growing phenomenon at this time. While many small businesses are beginning to use bar code for inventory control, paper file labeling, product indexing, etc., the needs for the low volume or occasional bar code user can only partially be met. While bar code reading devices are becoming very small and inexpensive, for example the credit card sized "Videx Time Wand" made by Videx, Inc., of Corvallis, Oreg., bar code printers remain awkward or expensive.
Programs exist to allow certain dot matrix printers to print bar code, but the print is of low quality which can cause errors in machine reading, and, as in address printing, the time needed to convert an existing letter printer to bar code label printing prohibits the printing of anything but a large number of labels. Additionally, these machines have a needlessly large "footprint", i.e , too much table space is used thereby relative to the small size of the labels used.
U.S. Pat. No. 4,264,396 to Stewart describes a hand held bar code printer now being marketed by Monarch Marking as the "Pathfinder" which, while small and convenient, is quite expensive due to its many features such as a self-contained microprocessor, fixed print head with many drivers, liquid crystal display, battery powered operation, built-in keyboard, label stripper, and label mounting mechanism. While the marketed printer can be interfaced with a host computer, this machine is intended primarily as a self-contained labeling machine and duplicates many features already found in personal computers.
Other bar code printers described in U.S. Pat. Nos. 4,516,208 to Sakura et al; 4,422,376 to Teraoka, and 4,432,830 to Jue are large, mechanically complicated, and include microprocessors, label separators, keyboards, and memory storage means. Their high price of these devices essentially restricts them to applications where many labels need to be printed.
None of the known systems provide a bar code printer which, in response to a field captured by the program, translates the data in the field for printing as a bar code.